write: change determination can user write to a terminal
Earlier test failed when user had write permission, but was not in special group that owns terminal devices, usually tty. This made write(1) to fail for root, if the root did not happen to be in tty group. In this commit root is granted ot write to anyone, even if they have mesg(1) turned off. For an user who is trying to write to own other session the group write bit is significant only for whether mesg(1) are enabled. Signed-off-by: Sami Kerola <kerolasa@iki.fi>
This commit is contained in:
parent
f7afb6b6b8
commit
0233a8ea18
|
@ -73,7 +73,7 @@ static void __attribute__ ((__noreturn__)) done(int);
|
||||||
int term_chk(char *, int *, time_t *, int);
|
int term_chk(char *, int *, time_t *, int);
|
||||||
int utmp_chk(char *, char *);
|
int utmp_chk(char *, char *);
|
||||||
|
|
||||||
static gid_t myegid;
|
static gid_t root_access;
|
||||||
|
|
||||||
static void __attribute__ ((__noreturn__)) usage(FILE * out)
|
static void __attribute__ ((__noreturn__)) usage(FILE * out)
|
||||||
{
|
{
|
||||||
|
@ -120,7 +120,7 @@ int main(int argc, char **argv)
|
||||||
usage(stderr);
|
usage(stderr);
|
||||||
}
|
}
|
||||||
|
|
||||||
myegid = getegid();
|
root_access = !getegid();
|
||||||
|
|
||||||
/* check that sender has write enabled */
|
/* check that sender has write enabled */
|
||||||
if (isatty(fileno(stdin)))
|
if (isatty(fileno(stdin)))
|
||||||
|
@ -299,8 +299,9 @@ int term_chk(char *tty, int *msgsokP, time_t * atimeP, int showerror)
|
||||||
return 1;
|
return 1;
|
||||||
}
|
}
|
||||||
|
|
||||||
/* group write bit and group ownership */
|
*msgsokP = !access(path, W_OK);
|
||||||
*msgsokP = (s.st_mode & (S_IWRITE >> 3)) && myegid == s.st_gid;
|
if (!root_access && *msgsokP)
|
||||||
|
*msgsokP = s.st_mode & S_IWGRP;
|
||||||
*atimeP = s.st_atime;
|
*atimeP = s.st_atime;
|
||||||
return 0;
|
return 0;
|
||||||
}
|
}
|
||||||
|
|
Loading…
Reference in New Issue